This application claims benefit of Japanese Application No. 2001-106174 filed on Apr. 4, 2001, the contents of which are incorporated by this reference.
1. Field of the Invention
The present invention relates to an endoscopic optical adapter freely attachable to and detachable from an endoscope in which a solid-state image device is placed in an endoscope-side observational optical system.
2. Description of Related Art
In recent years, endoscopes having a slender insertion portion have been used widely. These endoscopes are subjected to medical uses and industrial uses. Regarding the endoscope for the medical use, the insertion portion is inserted into a body cavity, and not only observation of organs in the body cavity, but also various therapiesxc2x7treatments are performed while endo-therapy products are introduced in the body cavity through an endo-therapy product channel provided in the aforementioned insertion portion, if necessary.
On the other hand, regarding the endoscope for the industrial use, the insertion portion is inserted into boilers, the inside of tubes in machines, chemical plants or the like, the inside of engines, or the like, and observation, inspection, repair, etc., are performed.
Examples of the aforementioned endoscopes include an electronic endoscope provided with an image device such as a charge coupled device (hereafter described as CCD), at the tip portion of the insertion portion. In this electronic endoscope, an endoscope image formed on the aforementioned image device can be displayed on the screen of a monitor and, therefore, observation can be performed.
Regarding the electronic endoscope (hereafter abbreviated as endoscope) for the industrial use, hitherto, a tip optical adapter which can be fitted to the tip portion of an endoscope, while being free to attach or detach, have been publicly known. Examples of the aforementioned tip optical adapters have included, for example, those which have changed the direction of view and those for binocular observation.
In the observational optical system of an endoscopic binocular optical adapter for binocular observation, a mask provided with two openings for splitting the observation image in two is placed. The optical images passed through the two openings of this mask form images on an image pickup surface of the image device. Therefore, on the screen of the monitor, the aforementioned two openings and the observation images passed through those openings are displayed.
However, the aforementioned mask has been configured to mechanically place in the optical adapter. Consequently, regarding positional relationship, the mask may be placed while being inclined relative to a predetermined condition depending on processing precision, etc., of members constituting the optical adapter.
When the aforementioned mask is placed in a condition of being inclined, as shown in FIG. 1, each side of the opening 101, which is an observation image displayed on the screen 100 of the monitor, becomes in a condition of being inclined at an angle xcex8 relative to each side of the screen 100.
Consequently, problems occur in quality of the observation image displayed on the screen of the monitor, and not limited to this, malfunctions may occur in observation and measurement due to occurrence of eclipse in the endoscope image when the inclination of the aforementioned mask is large.
It is an object of the present invention to provide an endoscope device capable of performing observation when an endoscope image is displayed on the screen of the monitor in the condition that endoscopic optical adapter is fitted to the endoscope, the observation image displayed on this screen becomes in a predetermined positional relationship relative to the screen, or to put it another way, for example, each side of the opening of the mask placed in the optical adapter and each side of the monitor screen are made in positional relationship of being parallel.
An endoscopic optical adapter freely attachable to and detachable from an endoscope according to the present invention is provided with an adapter-side observational optical system facing an endoscope-side observational optical system provided with a solid-state image device placed in a tip constituent member of the endoscope, a unit body in which the adapter-side observational optical system is fixedly placed, an adapter body on which a first concave portion with the unit body placed therein while being free to rotate and a second concave portion with at least a part of the tip constituent member placed therein are formed, and a positioning portion which is provided in each of the adapter body and the tip constituent member and which adjusts the positional relationship between the tip constituent member and the adapter body to be a predetermined positional relationship. Therefore, by rotating the unit body relative to the adapter body, the relative position of the adapter-side observational optical system placed in the unit body relative to the positioning portion is changed. That is, position adjustment of the adapter-side observational optical system relative to the positioning portion can be performed.
The above and other objects, features and advantages of the invention will become more clearly understood from the following description referring to the accompanying drawings.